Electromagnetic clutch.



W. C. HUEBNER.

ELEGTROMAGNETIG CLUTCH) APPLIOATION FILED SBPT.23,1912.

1,056,545. Patented Mar. 18, 1913.

being of the same;` polarity, while all of the strips on the other flange are of the opposite polarity.

. The driving member B of the clutch consists of av band or ring of non-magnetic niaterial, which is provided on its inner face with longitudinal slots g corresponding in number to the magnetic `strips E of the driven member, and in each of these slots is loosely confined a bar or armature H of soft iron or other magnetic material. These armatures extend throughout the width of the electromagnet D, across the two poles thereof and are free to move radially in lthe slots. Each of these armatures is so proportioned that its width circumferentially of the clutch is less than the width of the non-magnetic strips E of the magnet, so that the armatures cannot entirely bridge the gap between two adjacent magnetic strips E. As shown, the armatures H and the slotted part of the driving member B containing them project inwardly between edge portions of the side plates C and are held from lateral displacement thereby. The plates C have shoulders I which serve to hold the non-magnetic rings F in place, and the outer edges of the plates form bearings for the driving member of the clutch.

In the operation of the clutch, when the two members are uncoupled, the armatures H will be thrown outwardly in their pockets by centrifugal force, owing to the rotation of the driving member B and will thus be held out of contact with the driven member, permitting the free rotation of the driving member lliflien the magnet is energized by an exciting current in the coil d2 the armatures' will be dra-wn inwardly against the magnet, each armature contacting with two alined magnetic strips E of' opposite polarity of the magnet and thereby complet-ing a magnetic circuit between these two strips. By making the armatures H of a width less than the distance between the magnetic strips E of the magnet, the armatures may slip on the strips until they reach a `position adjacent to the edges of the strips approximately as shown in Fig. 3, but great force will be required to pull them out of contact with the strips, owing to the fact that the magnetic circuits would then have to be broken. ln this manner more torque can be excited by the driven member than if the armatures bridged the gaps between the magnetic strips, which would allow them to slip from one pair of strips to the next without breaking a magnetic circuit. By this construction a much greater torque can be produced in the clutch with a given amount of current, than in clutches in which the armatures bridge the space between adjacent magnetic strips, or in which the magnet-ic surface is not interrupted. By providing the clutch with a large number of magnetic strips and armatures, the slip or relative movementbetween the driving and driven members is reduced to a minimum and the clutch will take hold promptly and 4be very positive in action.

The clutch is eticieiit and reliable in operation, can be manufactured at a small cost and has no parts that are liable to get out of order.

I claim as my invention:

1. In a clutch, the combination of a rotatable magnet having a circular periphery composed of alternate magnetic. andnonmagnetic portions, a member which surrounds said magnet and is rotatable relative thereto, and armatures which are carried by said surrounding niemb'er and are movable radially thereon toward and from said magnet, substantially as set forth.

Q. In a clutch, the combination of a rotatable driven member comprising a magnet the poles of which have circular periplieries composed of alternate magnetic and noniiiagnetic portions, a rotatable driving member which surrounds said driven member, and armatures carried by said driving member which are movable inwardly and outwardly into and out of contact with the poles of said driven member, substantially as' set forth.

3. In a clutch, the combination of a rot-atable electromagnet comprising a magnetic core having circular end poles with alternate magnetic and non-magnetic peripheral portions, an exciting coil for said core, a rotatable member which surrounds said magnet, and armatures which are movable radially on said surrounding member toward and from said magnet core, substantially as set forth.

4. In a clutch, the combination of a driven member comprisingan electromagnet consisting of a magnetic core having end fianges with alternate magnetic and nonmagnetic peripheral portions, and an exciting coil surrounding said core between said flanges, a rotatable driving member sui'- rounding said driven member and having slots in its inner surface, and armatures movable radially in said slots, substantially as set forth.

5. In a clutch, the combination of a driven member comprising an electromagnet having circular end poles provided with alternate magnetic and non-magnetic peripheral 12m` portions, a `rotatable driving member surrounding said drivenmember, and armatures which are mounted on said driving member to move inwardly and outwardly toward and from said magnet, said armatures being of less width than the non-magnetic portions of said magnet poles, substantially as set forth.

6. In a clutch, the combination of a driven member comprising an electromag- 13G nethaving circular yend poles provided with peripheral slots, non-magnetic rings securedv on said magnet and'provided with spaced integral strips which occupy said peripheral slots in the magnet poles, a rotatable driving member surrounding said driven'member,' and armatures which are mounted on said driving member to vmove inwardly and outwardly toward and from said magnet, substantially as set forth.

Wit-ness my hand thisf`18th vdayof Septemoer, 1912. A

WILLIAM CARL HUEBNER. Witnesses:

EDWARD WmHELM', A..L. MGGEE. 

